1. Field of the Invention
The present invention relates generally to electrically operated fluid valves and relates specifically to valves used to control the flow of water to a washing machine or other appliance.
2. Description of the Related Art
Many modern appliances, such as washing machines, icemakers, and dishwashers, require a source of pressurized water for providing the appliance with water during its operation. Typically, the water is provided through a flexible hose connecting an inlet valve on the appliance to a water line, which is usually located in a wall near the appliance. In a washing machine, for example, the flexible hose limits the transfer of vibrations of the washer to the water line and allows for the washer to be moved short distances without disconnecting the hose from the water line. A manually operated valve is usually installed between a water hose and a water line, and a user can close the valve to prevent water from flowing through the hose when the hose is disconnected from the valve or the inlet of the appliance.
Each appliance typically has a control system that operates the inlet valves. In a washing machine, a user-operated timer mounted on the washing machine controls the cycling of the machine through the various functions in the washing process, the timer also opening the inlet valves when water is required in the machine. To allow for the washing machine to remain in a ready-to-use condition, the manual valve on each water line is usually left in the open position, water pressure remaining present in each water hose. This is also true for other appliances, providing the convenience of a ready-to-use appliance. The disadvantage to this is that a rupture of a water hose will allow water to escape, and, if undetected for an extended time, significant damage can result to the surrounding structure housing the appliance.
Several patents have been issued for devices used to address this problem. U.S. Pat. No. 5,918,617 to Garth discloses a system comprising a controller that controls electrically operated valves located at the water source. The controller opens and closes the valves in response to signals from the control system of an appliance, input from a moisture sensor located near the appliance, and the condition of a timer. Likewise, U.S. Pat. No. 5,934,302 to Nemelka discloses a microcontroller that senses current flow to an appliance, indicating that the appliance is in use, and opens water valves when current is flowing, the valves being installed upstream of the washing machine. The device also has pressure sensors for detecting an abnormal drop in the pressure in the water supply line. A similar device is disclosed in U.S. Pat. No. 6,003,536 to Polverari, et al., which has a controller for signaling valves to open when the controller detects the current draw of an appliance.
A leakage-detection system is disclosed in U.S. Pat. No. 5,992,218 to Tryba, et al., in which leak detectors are positioned near and/or in the appliance. The detectors are connected to a control apparatus that controls valves connected to the water supply. If a leak is detected, the control apparatus signals the valves to close, stopping the flow of water.
There is a need for an apparatus for preventing unwanted water flow through hoses connecting an appliance to a pressurized water supply that eliminates the need for a separate controller and power supply, the apparatus being electrically connected to the wiring of the appliance for relying only on the power to the inlet valve and the inlet valve control system of the appliance.
A safety valve is provided for an appliance using water from a pressurized water supply during operation of the appliance. The appliance has an electrically operated inlet valve connected to the water supply, the inlet valve being operated by a controller of the appliance. The safety valve has a valve body connected to the water supply upstream of the inlet valve, the valve body having a flow path for allowing water to flow through the valve body from the water supply to the inlet valve. The safety valve has an electrically operated solenoid and a valve gate connected to the solenoid. The valve gate is movably carried within the valve body, the gate being movable between a closed position that prevents water from flowing through the flow path and an open position that allows water to flow through the flow path. The solenoid is connected to the appliance, such that an electrical current from the control system to the inlet valve for opening the inlet valve is conducted to the solenoid for moving the gate to the open position. The gate is spring biased to the closed position for returning the gate to the closed position when the current ceases to flow.